3-(4-Chloro­phen­yl)-2,1-benzisoxazole-5-carbonyl chloride

The molecule of the title compound, C14H7Cl2NO2, is not planar; the dihedral angle between the mean planes of the chloro­phenyl and benzisoxazole rings is 20.32 (7)°. The carbonyl chloride group is twisted with respect to the benzisoxazole ring by 2.5 (1)°. The mol­ecular conformation is stabilized by an intra­molecular C—H⋯Cl hydrogen bond. In the crystal packing, adjacent mol­ecules are linked into dimers by inter­molecular C—H⋯O hydrogen bonds. The dimers are further stacked into columns along the unique axis direction by π–π stacking inter­actions, with a centroid⋯centroid distance of 3.828 (5) Å. Other weak inter­molecular C—H⋯O and C—H⋯Cl inter­actions are also present

Highly sensitive luminescence nanothermometry and thermal imaging facilitated by phase transition

Currently available temperature measurements or imaging at nano-micro scale are limited to fluorescent molecules and luminescent nanocrystals, whose spectral properties respond to temperature variation. The principle of operation of these conventional temperature probes is typically related to temperature induced multiphonon quenching or temperature dependent energy transfers, therefore, above 12%/K sensitivity and high thermal resolution remain a serious challenge. Here we demonstrate a novel class of highly sensitive thermographic phosphors operating in room temperature range with sub-kelvin thermal resolution, whose temperature readings are reproducible, luminescence is photostable and brightness is not compromised by thermal quenching. Corroborated with phase transition structural characterization and high spatio-temporal temperature imaging, we demonstrated that optically active europium ions are highly and smoothly susceptible to monoclinic to tetragonal phase transition in nanocrystalline (54 ± 14 nm) LiYO2 host, which is evidenced by changed number and the splitting of Stark components as well as by smooth variation of contribution between magnetic and electric dipole transitions. Further, reducing the size of phosphor from bulk to nanocrystalline matrix, shifted the phase transition temperature from 100 °C down to room temperature. These findings provide insights into the mechanism underlaying phase transition based luminescence nanothermometry and motivate future research toward new, highly sensitive, high temporal and spatial resolution nano-thermometers aiming at precise studying heat generation or diffusion in numerous biological and technology applications

Crystal structure of an organic–inorganic hybrid compound based on morpholinium cations and a β-type Anderson polyanion

A new organic–inorganic hybrid compound, pentamorpholinium hexahydrogen hexamolybdoferrate(III) sulfate 3.5-hydrate, (C4H10NO)5[FeIII(OH)6Mo6O18](SO4)·3.5H2O, was obtained from an aqueous solution. The polyoxidomolybdate (POM) anion is of the Anderson β-type with a central FeIII ion. Three of five crystallographically independent morpholinium cations are disordered over two sets of sites. An intricate network of intermolecular N—H...O and O—H...O interactions between cations, POMs, sulfate anions and non-coordinating water molecules creates a three-dimensional network structure

Crystal structure of tris(piperidinium) hydrogen sulfate sulfate

In the title molecular salt, 3C5H12N+·HSO4−·SO42−, each cation adopts a chair conformation. In the crystal, the hydrogen sulfate ion is connected to the sulfate ion by a strong O—H...O hydrogen bond. The packing also features a number of N—H...O hydrogen bonds, which lead to a three-dimensional network structure. The hydrogen sulfate anion accepts four hydrogen bonds from two cations, whereas the sulfate ion, as an acceptor, binds to five separate piperidinium cations, forming seven hydrogen bonds

Hypodiphosphoric acid and its inorganic salts

Hypodiphosphoric acid is the lower oxoacid of phosphorus of H4P2O6 composition. It contains the direct P—P bond, in contrast to its closest analog - pyrophosphoric acid, H4P2O7. In comparison to other phosphates the knowledge on hypodiphosphoric acid and its inorganic salts is quite limited. Since its discovery almost 150 years ago, establishment of the proper molecular and structural formula of the acid has initiated intensive research and dispute in the literature, which was decisively ended in 1964, when the first complete X-ray crystal structure determination of diammonium hypodiphosphate was reported. Since then structural studies have led to the discovery of ferroelectric properties in the above-mentioned diammonium salt and dehydration-induced staggerer-eclipsed transformation of hypodiphosphate in tetrabutylammonium salt, experimental electron density distribution determination in cubic tetralithium hexahydrate and last but not least crystal structure elucidation of hypodiphosphate analogs of adenosine diphosphate. In this mini-review the information on synthesis techniques, chemical and physical properties, applications of hypodiphosphates along with crystallochemical description of reported up-to-date crystal structures are presented

5-Iodo-3-phenyl-2,1-benzoxazole

The title compound, C13H8INO, was prepared by a condensation reaction of 4-nitrobenzene with phenylacetonitrile in NaOH–ethanol solution. There are two independent molecules in the asymmetric unit, in which the dihedral angles between the benzene ring and the benzoisoxazole unit are 4.2 (3) and 4.1 (3)°. The crystal packing is governed by C—H...N, C—I...π and C—I...O interactions

Crystal structure of O-isopropyl [bis(trimethylsilyl)amino](tert-butylamino)phosphinothioate

[Bis(trimethylsilyl)amino](tert-butylimino)thiophosphorane reacts in benzene with isopropyl alcohol via 1,2-addition of an iPrO–H bond across the P=N bond, resulting in the title compound, C13H35N2OPSSi2. In the molecule, the P atom possesses a distorted tetrahedral environment involving two N atoms from (Me3Si)2N– and tBuNH– groups, one O atom from an iPrO group and one S atom, therefore the molecule has a stereocenter on the P atom but crystal symmetry leads to a racemate. In the crystal, a pair of enantiomers form a centrosymmetric dimer via a pair of N—H...S hydrogen bonds